The two nearest harmonics of a tube closed at one end and open at other end are 220 Hz and 260 Hz. What is the fundamental frequency of the system?
NEET 2017 APRA
For the following questions answer them individually
A U tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of 10 mm above the water level on the other side. Meanwhile the water rises by 65 mm from its original level (see diagram). The density of the oil is
A particle executes linear simple harmonic motion with an amplitude of 3 cm. When the particle is at 2 cm from the mean position, the magnitude of its velocity is equal to that of its acceleration. Then its time period in seconds is
Two astronauts are floating in gravitational free space after having lost contact with their spaceship. The two will:
The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m, is
A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system
Which one of the following represents forward bias diode?
The photoelectric threshold wavelength of silver is $$3250 \times 10^{-10} m.$$ The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength $$2536 \times 10^{-10} m$$ is
(Given $$h = 4.14 \times 10^{-15} eVs and c = 3 \times 10^8 ms^{-1})$$
Two cars moving in opposite directions approach each other with speed of 22 m/s and 16.5 m/s respectively. The driver of the first car blows a horn having a frequency 400 Hz. The frequency heard by the driver of the second car is [velocity of sound 340 m/s]
Figure shows a circuit contains three identical resistors with resistance $$R = 9.0 Ω$$ each, two identical inductors with inductance L = 2.0 mH each, and an ideal battery with emf $$\epsilon = 18 V$$. The current 'I' through the battery just after the switch closed is
A beam of light from a source L is incident normally on a plane mirror fixed at a certain distance x from the source. The beam is reflected back as a spot on a scale placed just above the source L. When the mirror is rotated through a small angle $$\theta$$, the spot of the light is found to move through a distance y on the scale. The angle $$\theta$$ is given by
An arrangement of three parallel straight wires placed perpendicular to plane of paper carrying same current ‘I’ along the same direction is shown in Fig. Magnitude of force per unit length on the middle wire ‘B’ is given by
Young’s double slit experiment is first performed in air and then in a medium other than air. It is found that $$8^{th}$$ bright fringe in the medium lies where $$5^{th}$$ dark fringe lies in air. The refractive index of the medium is nearly
A spring of force constant k is cut into lengths of ratio 1 : 2 : 3. They are connected in series and the new force constant is $$k'$$. Then they are connected in parallel and force constant is $$k"$$. Then $$k' : k"$$ is
A thin prism having refracting angle $$10^\circ$$ is made of glass of refractive index 1.42. This prism is combined with another thin prism of glass of refractive index 1.7. This combination produces dispersion without deviation. The refracting angle of second prism should be
A gas mixture consists of 2 moles of $$O_2$$ and 4 moles of Ar at temperature T. Neglecting all vibrational modes, the total internal energy of the system is
Consider a drop of rain water having mass 1 g falling from a height of 1 km. It hits the ground with a speed of 50 m/s. Take g constant with a value
$$10 m/s^2$$. The work done by the (i) gravitational force and the (ii) resistive force of air is
The x and y coordinates of the particle at any time are $$x = 5t - 2t^2$$ and y = 10t respectively, where x and y are in meters and t in seconds. The acceleration of the particle at t = 2 s is
Two discs of same moment of inertia rotating about their regular axis passing through centre and perpendicular to the plane of disc with angular velocities $$\omega_1 and \omega_2.$$ They are brought into contact face to face coinciding the axis of rotation. The expression for loss of energy during this process is
Thermodynamic processes are indicated in the following diagram.
Match the following:
The bulk modulus of a spherical object is ‘B’. If it is subjected to uniform pressure ‘p’, the fractional decrease in radius is
The acceleration due to gravity at a height 1 km above the earth is the same as at a depth d below the surface of earth. Then
The diagrams below show regions of equipotentials.
A positive charge is moved from A to B in each diagram.
Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time $$t_1.$$ On other days, if she remains stationary on the moving escalator, then the escalator takes her up in time $$t_2.$$ The time taken by her to walk up on the moving escalator will be
Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively
A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be
Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are $$K_1 and K_2.$$ The thermal conductivity of the composite rod will be
One end of string of length l is connected to a particle of mass ‘m’ and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in circle with speed ‘v’, the net force on the particle (directed towards center) will be (T represents the tension in the string)
In a common emitter transistor amplifier the audio signal voltage across the collector is 3 V. The resistance of collector is $$3 kΩ$$. If current gain is 100 and the base resistance is $$2 kΩ$$, the voltage and power gain of the amplifier is
Which of the following statements are correct?
(a) Centre of mass of a body always coincides with the centre of gravity of the body.
(b) Centre of mass of a body is the point at which the total gravitational torque on the body is zero
(c) A couple on a body produce both translational and rotational motion in a body.
(d) Mechanical advantage greater than one means that small effort can be used to lift a large load.
A rope is wound around a hollow cylinder of mass 3 kg and radius 40 cm. What is the angular acceleration of the cylinder if the rope is pulled with a force of 30 N?
A long solenoid of diameter 0.1 m has $$2 \times 10^4$$ turns per meter. At the centre of the solenoid, a coil of 100 turns and radius 0.01 m is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to 0 A from 4 A in 0.05 s. If the resistance of the coil is $$10 \pi^2 Ω$$, the total charge flowing through the coil during this time is
The ratio of wavelengths of the last line of Balmer series and the last line of Lyman series is
Suppose the charge of a proton and an electron differ slightly. One of them is -e, the other is $$(e + \triangle e)$$. If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero, then $$\triangle e$$ is of the order of [Given mass of hydrogen $$m_h = 1.67 \times 10^{-27}$$ kg]
The given electrical network is equivalent to
A Carnot engine having an efficiency of $$\frac{1}{10}$$ as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lower temperature is
In an electromagnetic wave in free space the root mean square value of the electric field is $$E_rms = 6 V/m$$. The peak value of the magnetic field is
Two Polaroids $$P_1 and P_2$$ are placed with their axis perpendicular to each other. Unpolarised light $$I_0$$ is incident on $$P_1$$. A third polaroid $$P_3$$ is kept in between $$P_1 and P_2$$ such that its axis makes an angle $$45^\circ$$ with that of $$P_1$$. The intensity of transmitted light through $$P_2$$ is
If $$\theta_1 and \theta_2$$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip $$\theta$$ is given by
A 250-Turn rectangular coil of length 2.1 cm and width 1.25 cm carries a current of $$85 \mu A$$ and subjected to a magnetic field of strength 0.85 T. Work done for rotating the coil by $$180^\circ$$ against the torque is
The resistance of a wire is ‘R’ ohm. If it is melted and stretched to ‘n’ times its original length, its new resistance will be
A physical quantity of the dimensions of length that can be formed out of c, G and $$\frac{e^2}{4 \pi \epsilon_0}$$ is [c is velocity of light, G is universal constant of gravitation and e is charge]
Radioactive material 'A' has decay constant $$'8 \lambda'$$ and material 'B' has decay constant $$'\lambda'$$. Initially they have same number of nuclei. After what time, the ratio of number of nuclei of material 'B' to that 'A' will be $$\frac{1}{e}$$ ?
A potentiometer is an accurate and versatile device to make electrical measurements of E.M.F, because the method involves :
The ratio of resolving powers of an optical microscope for two wavelengths $$\lambda_1 = 4000 Å$$ and $$\lambda_2 = 6000 Å$$ is
A disease caused by an autosomal primary non-disjunction is
A dioecious flowering plant prevents both:
Attractants and rewards are required for
Alexander Von Humboldt described for the first time
Which of the following cell organelles is responsible for extracting energy from carbohydrates to form ATP?
Zygotic meiosis is characterstic of
Good vision depends on adequate intake of carotene rich food
Select the best option from the following statements
(a) Vitamin A derivatives are formed from carotene
(b) The photopigments are embedded in the membrane discs of the inner segment
(c) Retinal is a derivative of vitamin A
(d) Retinal is a light absorbing part of all the visual photopigments
Among the following characters, which one was not considered by Mendel in his experiments on pea?
The association of histone H1 with a nucleosome indicates:
The pivot joint between atlas and axis is a type of
Receptor sites for neurotransmitters are present on
Gn RH, a hypothalamic hormone, needed in reproduction, acts on
Hypersecretion of Growth Hormone in adults does not cause further increase in height, because
Select the mismatch :
Which one of the following statements is not valid for aerosols?
Which one of the following is related to Ex-situ conservation of threatened animals and plants?
Which of the following facilitates opening of stomatal aperture?
Select the mismatch :
Asymptote in a logistic growth curve is obtained when
The process of separation and purification of expressed protein before marketing is called
The water potential of pure water is
The function of copper ions in copper releasing IUD's is :
Double fertilization is exhibited by
Presence of plants arranged into well defined vertical layers depending on their height can be seen best in :
Which ecosystem has the maximum biomass?
Root hairs develop from the region of
DNA replication in bacteria occurs
Homozygous purelines in cattle can be obtained by
In Bougainvillea thorns are the modifications of
A decrease in blood pressure/volume will not cause the release of
Which statement is wrong for Krebs' cycle?
Anaphase promoting complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cells. If APC is defective in a human cell, which of the following is expected to occur?
Which of the following options best represents the enzyme composition of pancreatic juice?
Life cycle of Ectocarpus and Fucus respectively are
Which of the following is made up of dead cells?
Which of the following is correctly matched for the product produced by them?
Fruit and leaf drop at early stages can be prevented by the application of
Viroids differ from viruses in having :
Which of the following are not polymeric?
A temporary endocrine gland in the human body is
Phosphonol pyruvate (PEP) is the primary $$CO_2$$ acceptor in :
Plants which produce characterstic pneumatophores and show vivipary belong to
Mycorrhizae are the example of
If there are 999 bases in an RNA that codes for a protein with 333 amino acids, and the base at position 901 is deleted such that the length of the RNA becomes 998 bases, how many codons will be altered?
A gene whose expression helps to identify transformed cell is known as
Which of the following are found in extreme saline conditions?
Out of 'X' pairs of ribs in humans only 'Y' pairs are true ribs. Select the option that correctly represents values of X and Y and provides their explanation :
MALT constitutes about ___________ percent of the lymphoid tissue in human body
Which one from those given below is the period for Mendel's hybridization experiments?
Adult human RBCs are enucleate. Which of the following statement(s) is/are most appropriate explanation for this feature?
(a) They do not need to reproduce
(b) They are somatic cells
(c) They do not metabolize
(d) All their internal space is available for oxygen transport
Myelin sheath is produced by
Which of the following statements is correct?
During DNA replication, Okazaki fragments are used to enlongate
Which one of the following statements is correct, with reference to enzymes?
DNA fragments are
The DNA fragments separated on an agarose gel can be visualised after staining with
Which among the following are the smallest living cells, known without a definite cell wall, pathogenic to plants as well as animals and can survive without oxygen?
The morphological nature of the edible part of coconut is
Select the correct route for the passage of sperms in male frogs :
Identify the wrong statement in context of heartwood.
Transplantation of tissues/organs fails often due to non-acceptance by the patient's body. Which type of immune-response is responsible for such rejections?
The region of Biosphere Reserve which is legally protected and where no human activity is allowed is known as
Thalassemia and sickle cell anemia are caused due to a problem in globin molecule synthesis. Select the correct statement.
Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by
An important characteristic that Hemichordates share with Chordates is
Which of the following options gives the correct sequence of events during mitosis?
The final proof for DNA as the genetic material came from the experiments of
What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis?
With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct?
Artificial selection to obtain cows yielding higher milk output represents
Which of the following in sewage treatment removes suspended solids?
Spliceosomes are not found in cells of
Functional megaspore in an angiosperm develops into
Which of the following components provides sticky character to the bacterial cell?
Which among these is the correct combination of aquatic mammals?
Which of the following represents order of 'Horse'?
Lungs are made up of air-filled sacs the alveoli. They do not collapse even after forceful expiration, because of :
Capacitation occurs in
Which of the following RNAs should be most abundant in animal cell?
Which cells of 'Crypts of Lieberkuhn' secrete antibacterial lysozyme?
In case of a couple where the male is having a very low sperm count, which technique will be suitable for fertilisation?
Frog's heart when taken out of the body continues to beat for some time
Select the best option from the following statements
(a) Frog is a poikilotherm
(b) Frog does not have any coronary circulation
(c) Heart is "myogenic" in nature
(d) Heart is autoexcitable
Match the following sexually transmitted diseases (Column - I) with their causative agent (Column - II) and select the correct option.
The genotypes of a Husband and Wife are I A I B and I A i. Among the blood types of their children, how many different genotypes and phenotypes are possible?
The hepatic portal vein drains blood to liver from
Coconut fruit is a
The vascular cambium normally gives rise to
In case of poriferans the spongocoel is lined with flagellated cells called :
A baby boy aged two years is admitted to play school and passes through a dental check-up. The dentist observed that the boy had twenty teeth. Which teeth were absent?
An example of colonial alga is
An example of a sigma bonded organometallic compound is
Which one is the correct order of acidity?
Predict the correct intermediate and product in the following reaction
It is because of inability of $$ns^2$$ electrons of the valence shell to participate in bonding that
Ionic mobility of which of the following alkali metal ions is lowest when aqueous solution of their salts are put under an electric field?
Match the interhalogen compounds of column I with the geometry in column II and assign the correct code
Which is the incorrect statement?
Which one of the following statements is not correct?
In the electrochemical cell
$$Zn \mid ZnSO_4 (0.01M)\parallel CuSO 4 (1.0 M)\mid Cu$$, the emf of this Daniel cell is $$E_1$$. When the concentration of $$ZnSO_4$$ is changed to 1.0 M and that of $$CuSO_4$$ changed to 0.01 M, the emf changes to $$E_2$$. From the following, which one is the relationship between $$E_1 and E_2$$ ?
(Given, $$\frac{RT}{F} = 0.059$$)
The correct statement regarding electrophile is
The correct order of the stoichiometries of AgCl formed when $$AgNO_3$$ in excess is treated with the complexes : $$CoCl_3.6NH_3, CoCl_3.5NH_3, CoCl_3.4NH_3$$ respectively is
The IUPAC name of the compound
The species, having bond angles of $$120^\circ$$ is
The equilibrium constants of the following are
$$N_2 + 3H_2 \rightleftharpoons 2NH_3 K_1$$
$$N_2 + O_2 \rightleftharpoons 2NO K_2$$
$$H_2 + \frac{1}{2} O_2 \rightarrow H_2O K_3$$
The equilibrium constant (K) of the reaction
Name the gas that can readily decolourises acidified $$KMnO_4$$ solution:
The most suitable method of separation of 1 : 1 mixture of ortho and para-nitrophenols is
The reason for greater range of oxidation states in actinoids is attributed to
The element Z = 114 has been discovered recently. It will belong to which of the following family group and electronic configuration?
Mechanism of a hypothetical reaction $$X_2 + Y_2 \rightarrow 2XY is given below:
(i) X_2 \rightarrowX + X (fast)
(ii) X + Y_2 \rightleftharpoons XY + Y (slow)
(iii) X + Y \rightarrow XY (fast)
The overall order of the reaction will be
If molality of the dilute solution is doubled, the value of molal depression constant $$(K_f)$$ will be
With respect to the conformers of ethane, which of the following statements is true?
The heating of phenyl-methyl ethers with HI produces.
The correct increasing order of basic strength for the following compounds is
In which pair of ions both the species contain S - S bond?
Which of the following is dependent on temperature?
Of the following, which is the product formed when cyclohexanone undergoes aldol condensation followed by heating?
Mixture of chloroxylenol and terpineol acts as
For a given reaction, $$\triangle H = 35.5 kJ mol^{-1} and \triangle S = 83.6 JK^{-1} mol^{-1}$$. The reaction is spontaneous at : (Assume that $$\triangle H and \triangle S$$ do not vary with temperature)
$$HgCl_2 and I_2$$ both when dissolved in water containing $$I^-$$ ions the pair of species formed is
A first order reaction has a specific reaction rate of $$10^{-2} s^{-1}$$. How much time will it take for 20 g of the reactant to reduce to 5 g?
Which one is the most acidic compound?
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $$Co^{3+}$$ is
Concentration of the $$Ag^+$$ ions in a saturated solution of $$Ag_2C_2O_4$$ is $$2.2 \times 10^{-4} mol L^{-1}$$. Solubility product of $$Ag_2C_2O_4$$ is
A 20 litre container at 400 K contains $$CO_2 (g)$$ at pressure 0.4 atm and an excess of SrO (neglect the volume of solid SrO). The volume of the containers is now decreased by moving the movable piston fitted in the container. The maximum volume of the container, when pressure of CO 2 attains its maximum value, will be
(Given that : $$SrCO_3(s) \leftharpoondown SrO(s) + CO_2(g).K_p = 1.6$$ atm)
Identify A and predict the type of reaction
Which of the following reactions is appropriate for converting acetamide to methanamine?
Which of the following pairs of compounds is isoelectronic and isostructural?
Which of the following is a sink for CO?
Which one of the following pairs of species have the same bond order?
A gas is allowed to expand in a well insulated container against a constant external pressure of 2.5 atm from an initial volume of 2.50 L to a final volume of 4.50 L. The change in internal energy $$\triangle U$$ of the gas in joules will be
Extraction of gold and silver involves leaching with $$CN^-$$ ion. Silver is later recovered by
Consider the reactions :
Identify A, X, Y and Z
Pick out the correct statement with respect $$[Mn(CN)_6]^{3-}$$:
Which one is the wrong statement?
Which of the following statements is not correct?
